Mickey's age is 4 years less than $300\%$ of Jerry's age. If Mickey is 14 years old, how old is Jerry?
Explanation: Let $M$ and $J$ be the ages of Mickey and Jerry, respectively.  Then, $300\%$ of Jerry's age is $3J$.  Since Mickey's age is 4 years less than $300\%$ of Jerry's age, we have $M=3J - 4$.  We are given that $M = 14$, so $14 = 3J-4$.  Adding 4 to both sides gives $18 = 3J$, so $J=6$ and Jerry is $\boxed{6}$ years old.